Police are highlighting the dangers of sniffing butane after a 12-year-old boy was found dead in a car park in the eastern Christchurch suburb of New Brighton on Friday night.

The boy was with a group of young people who had been sniffing the flammable hydrocarbon gas from a canister, police say.

The boy, who has not been named yet, died in a New Brighton car park after attempts by ambulance staff failed to resuscitate him.

No one is being sort in connection to his death, which has been referred to the coroner.

A post-mortem examination will be carried out on Monday.

Police are looking into how the group got hold of the butane and have issued a warning about inhaling the substance.

"While the cause of death has yet to be confirmed, the incident highlights the dangers of people sniffing butane or `huffing' as it is known," police said.